Friday, June 7, 2013

Chase Log - 5-28-2013 Bennington, KS Tornadoes

What a day! After the incredible chaser convergence and brief views of 2 tornadoes the day before in north-central KS, we headed back down to Salina for the night. Met Brandon Sullivan, Brett Wright, and Gary Schmitt for lunch...and finally met Roger Hill there, as well. Models were pretty well in agreement in showing a small but significantly potent tornado threat just north of Salina, where an outflow boundary would intersect with a deepening low pressure center and southward extending dryline.

We left, activated a US Cellular data card, and sat just east of Salina for a while. As we were waiting, met up with Matt Phelps and ETT for a bit, then left as towers started to fire. Headed over to Abilene, and watched the dryline bubble. Finally, a cluster of updrafts fired and moved slowly to the northeast. We headed west towards it, stopping for 20 minutes or so to watch it organize. As we did, an incredible mammatus show appeared overhead!

By far the best mammatus I've ever seen...myself and Ellie just sat on the hood of the Jetta and watched it for a while. Then, as the core of the supercell started to organize rapidly, we blasted west to get a better view of the meso.

As we approached, a large wall cloud became apparent...

This wall cloud dropped a brief tornado as we approached it. We pulled over on the side of the road about  a mile or so west of Bennington, KS. What followed was the most amazing tornado I've ever witnessed...

The mesocyclone recycled, and a second wall cloud started to take shape to the northeast. Here's a radar shot with our position indicated by the white circle...GPS integrated into the radar software.

At this point, the storm stalled. Literally. No forward motion at all. At this point, it was obvious that it was just a matter of time until a big tornado was going to form. Rotation from the second wall cloud was unbelievably rapid.

The structure was incredible...look at the mid-level inflow bands wrapping around from the southeast into the wall cloud at the top-center of the picture! These feeder bands would eventually extend for miles south of the storm, injecting it with primed warm, moist air to feed on.

Several scuddy funnels started to drop from the wall cloud as tornadogenesis became imminent...

And then, a massive cone drops from the skies above.

The tornado partially wrapped itself in rain several times during the early stages of its' life cycle, all the while slowly growing into a monster.

Then, incredibly, the tornado emerged completely from the surrounding rain curtains, and entered what would be its' most photogenic phase.

The tornado then wedged out to over a mile wide, and became almost completely rain-wrapped. I swung east about a mile to get shots of the meso above...

We got a couple more good video shots while the tornado was over a mile wide.

The tornado eventually occluded and dissipated, deep in the rain curtains, after being on the ground for over 45 minutes! It was rated EF-4 due to wind speed measurements from the DOW. And, it was Ellie's first good Plains tornado!

UPDATE: Finished editing the video, here's the final work!